Self-propelled ground milling machines are used for milling the underlying ground. What these machines have in common is that they have as a working device a milling drum carried by a machine frame, which milling drum is lowered into the subgrade soil in working operation and is guided in the soil along the milling track by the advancing machine. The milling drum, which comprises a plurality of milling devices on its outside jacket surface, rotates in working operation about an axis of rotation extending horizontally and transversely to the working direction. The lowering may occur, for example, by a lowering of the machine frame or by a lowering relative to the machine frame. The milling drum is mounted in a milling drum box, which is connected with the machine frame, for example. The ground milling machines relevant in the present context are self-propelled, i.e., travel by means of self-propulsion. Road milling machines, in particular, so-called road cold milling machines, are used for the milling, grinding and removal of road pavement layers, for example, asphalt and concrete layers. A generic road milling machine, in particular, of the large milling machine type, is described in DE 10 2012 019 016 A1, for example, which is herewith incorporated herein by reference. Stabilizers and recyclers are used for the milling of subgrade soil material, the blending of binders and/or water into the subgrade soil and/or the recycling of subgrade soil material, for example, in road and path construction. Such machines are described in DE 10 2013 020 679 A1, which is also incorporated herein by reference. So-called surface miners, on the other hand, are sometimes very large machines and are used for the extraction of natural resources, in particular, in surface mining operation. A typical surface miner is described in U.S. Pat. No. 6,276,758 B1, which is herewith incorporated herein by reference.
Ground milling machines, in particular, road milling machines, recyclers, stabilizers or surface miners, normally have large dimensions and a partly contorted configuration, so that it is often difficult for operators to reach all relevant positions for maintenance purposes, for example. This regularly applies, in particular, to the drive engine in the engine compartment, which usually requires a large amount of maintenance work and whose maintenance points are often difficult to reach. The drive engine is usually an internal combustion engine which is arranged in the interior of the ground milling machine, for example, mounted on a machine frame. An arrangement space is provided for this purpose, which is designated in the present case as the engine compartment. For protective purposes and/or for noise insulation, the engine compartment is frequently implemented as covered. The drive engine is thus not exposed, but is protected from the ambient environment. The entirety of said covering structure will be designated below as the engine compartment enclosure. The covering of the engine compartment occurs especially at least to the sides (in the horizontal direction) and upwardly in the vertical direction. It is now necessary for maintenance work that the operator is granted access from the outside to the interior space of the engine compartment in order to service the drive engine. The engine compartment enclosure frequently comprises a cover for this purpose which is adjustable between a covering position and a maintenance position. The cover is thus part of the engine compartment enclosure and designates an adjustable flat element which in its maintenance position releases an opening for access to the engine compartment from the outside. Such a cover is regularly a bonnet or an engine cover flap.
It is common practice, especially in the case of self-propelled ground milling machines of large dimensions, that maintenance occurs from an operator platform. The operator platform designates the location from which the operation of the ground milling machine occurs in working operation. In order to reach all points that are relevant for maintenance, floor surfaces are frequently arranged in the interior of the engine compartment on which the operator, coming from the operator platform, can stand within the engine compartment. This solution is, however, disadvantageous in several respects. On the one hand, the available space within the engine compartment is very small. On the other hand, there is a constant risk that the operator will access positions which are not intended for this purpose, thus causing damage to the engine or the respective elements within the engine compartment. Moreover, there is further a considerable risk of injury to the operator, e.g., by contact with hot engine parts, sharp cutting edges, etc.